Systems and methods are configured for power distribution in a hybrid fixed-wing VTOL drone aircraft. A drone aircraft includes two modes of operation. In a first mode of operation, the internal combustion engine is shut off while an electric motor-based VTOL system provides lift and thrust. In a second mode of operation, an internal combustion engine provides thrust while a set of fixed wings provide lift. In the second mode of operation, mechanical power from the internal combustion engine provides for power generation to charge an electrical battery to power the electric motor-based VTOL system.

A propulsion system for an aircraft can include an electric power source and an electric propulsion assembly having an electric motor and a propulsor. The propulsor can be powered by the electric motor. An electric power bus can electrically connect the electric power source to the electric propulsion assembly. The electric power source can be configured to provide electrical power to the electric power bus. An inverter converter controller can be positioned along the electric power bus and can be electrically connected to the electric power source at a location downstream of the electric power source and upstream of the electric propulsion assembly.

Propulsion system (2) for a helicopter (1) comprising a main engine (9), a main rotor (3), a main gearbox (4) including an output mechanically connected to the main rotor (3), a reduction gearbox (13) mechanically coupled between the main engine (9) and a first input of the main gearbox (4), and an assistance device (10).

The assistance device (10) comprises a first electric machine mechanically coupled to the reduction gearbox (13) and configured to operate as an electric generator to take off energy produced by the main engine (9), and a second electric machine mechanically coupled to a second input of the main gearbox (4), the second electric machine being supplied with electrical power by the first electric machine and configured to operate as an electric motor to deliver additional mechanical power to the main gearbox (4).

A system and method for slowing the rotation of a rotor using, for example, rotor brake system for a rotorcraft comprises: one or more generators connected to a main rotor gearbox; an electric distributed anti-torque system mounted on a tail boom of the rotorcraft comprising two or more electric motors connected to the one or more generators, wherein the two or more electric motors are connected to one or more blades; and wherein a rotation of the rotor is slowed by placing a drive load on the main rotor gearbox with the one or more generators to bleed the mechanical power from rotor into electrical power via the two or more electric motors, wherein the electric distributed anti-torque system generates thrust in opposing directions.

Series hybrid propulsion unit including a gas turbine driving a mechanical shaft of an electric generator having n output phases and supplying an AC busbar, and a system for monitoring the speed of the gas turbine, the AC busbar supplying a plurality of AC distribution channels each composed of an electric rectifier and a battery sharing the power required to supply a DC bus, the DC bus in turn supplying a plurality of propulsion sub-channels composed of electric inverters supplying, under the monitoring of a control module, motors driving thrusters, further including a battery charger for charging the battery from the DC bus, a power management module delivering a power reference for the electric generator, and a hybridization rate management module monitoring the voltage of the DC bus, the battery being directly connected on the DC bus via a passive component and the electric rectifier being a passive converter.

A tailsitter aircraft includes an airframe, a thrust array attached to the airframe and a flight control system. The thrust array includes propulsion assemblies configured to transition the airframe from a forward flight orientation to a VTOL orientation at a conversion rate for an approach to a target ground location in a forward flight-to-VTOL transition phase. The flight control system implements an adaptive transition system including a transition parameter monitoring module configured to monitor parameters including a ground speed and a distance to the target ground location. The adaptive transition system includes a transition adjustment determination module configured to adjust the conversion rate of the airframe from the forward flight orientation to the VTOL orientation based on the ground speed and the distance to the target ground location such that the airframe is vertically aligned with the target ground location in the VTOL orientation of the forward flight-to-VTOL transition phase.

A voltage converter for an aircraft electrical system includes an input power line configured to receive input electrical power, an output power line configured to supply output electrical power to aircraft loads, conversion circuitry, and a controller. The conversion circuitry is configured to convert the input electrical power to supply the output electrical power based on one or more control parameters. The controller is configured to receive data relating to the aircraft loads and modify at least one control parameter based on the data.

A method of optimizing the noise generated by a hybrid power plant of a rotorcraft in flight, the hybrid power plant driving a main rotor of the rotorcraft in rotation and being provided with at least one engine, with at least one electric machine, and with at least one electrical energy source that electrically powers the electric machine. The method includes a determination step for determining a required power delivered by the hybrid power plant and that is required for the flight phase, and a distribution step for distributing the required power between the at least one engine and the electric machine as a function of a target noise level and of the required power for the flight phase, as well as of a model for the noise generated by the at least one engine as a function of one of its parameters.

Reconfigurable permanent magnet electrical machines and aircraft power and propulsion systems including the electrical machines. An aircraft power and propulsion system includes: a gas turbine engine; DC electrical network; permanent magnet electrical machine including a rotor drivingly coupled to a spool of the engine, and a stator including windings controllably switchable between a star and a delta configuration; an AC-DC power electronics converter, an AC side is connected to terminals of the stator windings and a DC side is connected to the DC electrical network; an additional electrical power source connected to and controllable to supply electrical power to the DC electrical network; and a control system configured to control the switching of the stator windings between the configurations and to control the additional electrical power source to supply electrical power to the DC electrical network during a time interval when the stator is being switched between the configurations.

Integrated arrangements of electrical machines and power electronics converters are described. One such arrangement comprises: an electrical machine comprising one or more windings; a power electronics converter arranged to supply current to or receive current from the one or more windings of the electrical machine; a magnetocaloric effect (MCE) material in thermal contact with the power electronics converter; and a heat sink for removing heat from the MCE material. The MCE material is arranged in proximity to the one or more windings of the electrical machine whereby, in use, stray magnetic flux from the windings of the electrical machine passes through the MCE material and activates the MCE material. The repeated application and removal of the stray flux during normal operation of the electrical machine creates cycles of magnetic refrigeration, which removes heat from the power electronics converter.